Wireless communication networks typically include wireless communication devices which, via a wireless access node, communicate with further communication networks and equipment. Recently, a growing demand for mobile high speed data transfers has resulted in the development of several internet protocol (IP) mobility protocols. These IP mobility solutions attempt to solve the problem of a wireless communication device roaming within a network by providing location-independent routing of data packets.
One IP mobility standard is Mobile IP, which is typically utilized in third generation (3G) wireless access networks. Under Mobile IP, a wireless communication device is associated with a home wireless network and an anchored home IP address. The home wireless network includes a home agent that stores information about the wireless communication device. When the wireless communication device roams into a foreign wireless network, the device is associated with a care-of-address which identifies its current location, and the home address is associated with the local endpoint of a tunnel to the home agent. Mobile IP specifies how a wireless communication device registers with its home agent and how the home agent routes packets to and from the wireless device through the tunnel.
Simple IP is another example of an IP mobility solution typically employed in fourth generation (4G) wireless networks. Under the simple IP protocol, a wireless communication device receives a dynamic IP from a local access router in a visited wireless network, and the visited wireless network provides a direct routing service for the wireless communication device. Unless the wireless communication device requires a static IP address, a new IP address is typically acquired (and existing connections are lost) every time the device changes its point of attachment.
While the standard IP mobility protocols work well when roaming within different subnets of a network or within different networks utilizing the same IP mobility scheme, a problem arises when a static IP address is required for a dual-mode wireless communication device capable of communicating with two different wireless access networks. For example, 3G and 4G wireless networks are typically built on fundamentally different access technologies and handle static IP address assignment using different techniques. However, when a user of a dual-mode wireless communication device subscribes to a static IP service, the device should always receive the same static IP address, regardless of whether the device accesses a 3G network or a 4G network.